This is a hard one to comment on in one or two sentences. But, let me give you my honest opinion, short and sweet.
Many men and women go through what you are going through right now at some point in their relationship. It's normal.
The question is: Are you happy? Do you feel fulfilled? If you're not (and it sounds like you're not) you should discuss it with your husband. Chances are he is not happy either.
Try to find ways to get the spark back in your relationship. If it does not work then at least you know that you have tried and can stop blaming yourself.